ABSTRACT
We considered the problem of minimization of a functional I on a convex subset U of a Banach space in Chapter 1. The necessary condition of minimum at a point u is the variational inequality ⟨ I ′ ( u ) , v - u ⟩ ≥ 0 ∀ v ∈ U , $$ \begin{aligned} \langle I^{\prime }(u),v-u\rangle \, \ge \,0\;\forall v\in U, \end{aligned} $$ https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781315152448/5968d418-c0e2-45a5-91c4-37245a5e7358/content/math4_1.tif"/>
